Charging a battery?

I got one of eBay for a Volkswagen. It works just like you describe, the only things you have to watch for is don't use it when the engine is running (DUH!) and make sure the cig. lighter works with the ignition off.

For the most part, I don't think it generates enough charge to damage the internal wires of the vehicle.

RJ in WV

Yes you would turn the cable into a toaster, or pop a fuse.

You need: Some way to limit the current into the battery, a blocking diode, and matched wire AWG size.

Easist way would be to set up the battery with wires that match the existing AWG of the wires to the battery and install a battery isolator.

Cheers

I should note the one I have is a solar charger.

Sorry,

RJ in WV

>

I should note that I understood the question to be different from the rest of you. Sounds like the OP is asking about charging an extra battery, in the passenger compartment, using power provided by the cig. lighter. I may be wrong, and will shove a foot in my mouth if so (virtually of course), but that's what I read.

On that note, I'm pretty sure the emergency, self-contained jump-start units will charge off the cig lighter. Some units will also reverse the flow of electricity and re-charge the car battery if needed, enough to start the car, others will attach to the battery like jump-starting from another vehicle...

---SNIP ----

You're right, I didn't read it correctly.

I hope the OP doesn't smoke if the battery is in the passenger compartment.

RJ in WV

i guess it depends on what the spare battery is for and how often it's needed... i think you're looking for trouble trying to charge it from the cig lighter, tho.. however, if it's say a spare battery that you carry in the back of the pickup for jump starts or something, you could use a cheap power inverter and a 110v trickle charger.. i have a solar charger on my trailer battery... keeps it from going down when the trailer is in storage... you might try that way, also, it was like $30 at harbor freight...

I AM looking to charge a spare battery in the passenger compartment...Iv already got dual batterys under the hood but dont want to drain them down with the cooler (see below)

I bought one of those electric coolers and it runs off 12v outlet from the vehicle. i also have a spare battery i bought a while ago just sitting idle. what i was hoping to do was use the battery while im camping at night to keep the cooler running and when i start driving around, charge that battery (while the cooler is hooked into another cig lighter). I wasnt too keen on keeping it plugged into the vehicle overnight because it draws about

5amps. it will kill a battery in about 6-8 hours. im also in the process of locating a battery cutoff (stops the flow of power when the voltage drops to

compartment.

For running a cooler overnight you'd be better off buying or scrounging a deep cycle marine battery or a deep cycle caravan battery that is designed for that sort of use. A normal car/truck battery is designed to provide tons of power for a short period to crank the starter. and then filter the alternator power, Not to sustain a small draw for long periods.

rhys

Bob, what you need to get is a isolated relay. it seperates the batteries at idle but when you turn on the key it activates the relay and jumps the two batteries together so both charge while driving.

Colorado Springs, CO My advice may be worth what you paid for it.